GARBA 178Mo

GARBA 178Mo is a general-purpose austenitic stainless steel that is used for springs and other components requiring good fatigue resistance and good resistance against atmospheric corrosion. Addition of molybdenum increases the tensile strength as compared to GARBA 188 and also increases the resistance against localised and general corrosion.

Chemical composition

C
(%)

Si
(%)

Mn
(%)

P
max. (%)

S
max. (%)

Cr
(%)

Ni
(%)

Mo
(%)

0.05 -
0.15

2.00

2.00

0.045

0.015

16.00 -
19.00

6.00 -
9.50

0.80

Mechanical properties

For round wire

Diameter (mm)

Tolerance (± mm)

Tensile Strength (N/mm²)

0.30 -
0.65

0.008

-

0.66 -
1.01

0.010

-

1.02 -
2.26

0.015

-

2.27 -
4.01

0.020

-

4.02 -
6.26

0.025

-

6.27 -
8.00

0.030

-

0.30 -
0.40

2250 - 2590

0.41 -
0.50

2200 - 2530

0.51 -
0.65

2150 - 2470

0.66 -
0.80

2100 - 2420

0.81 -
1.00

2050 - 2360

1.01 -
1.25

2000 - 2300

1.26 -
1.50

1950 - 2240

1.51 -
1.75

1900 - 2190

1.76 -
2.00

1850 - 2130

2.01 -
2.50

1750 - 2010

2.51 -
3.00

1700 - 1960

3.01 -
3.50

1650 - 1900

3.51 -
4.25

1600 - 1840

4.26 -
5.00

1550 - 1780

5.01 -
6.00

1500 - 1730

6.01 -
7.00

1450 - 1670

7.01 -
8.00

1400 - 1610

Surface conditions

Surface performanceAC-surface 0.30–8.00 mm Ø. The AC-coating can be removed before heat treatment by using a 10-20% nitric acid pickle at room temperature.

E and G modulus of shear

Heat conductivity

Resistivity

Temperature oC

20

100

200

300

nΩm

700

750

800

950

Linear expansion

Pro °C

30–100

30–200

30–400

x10 –6

17.0

17.5

18.5

Specific heat capactity

Temperature oC

20

100

200

400

J/(kg* oC)

440

480

520

560

Recommendations

Heat treatment

As soon as possible after coiling, the springs should be stress relieved. Recommended temperature for compression springs or tension springs without initial tension is approx. 420 ºC for 0.5 - 4 hours.